Welcome GCC 8.1, the first release of the GCC 8 series!

https://gcc.gnu.org/gcc-8/changes.html has a comprehensive overview of
many changes in this release and https://gcc.gnu.org/gcc-8/porting_to.html
addresses issues you may encounter porting to this new version.

To provide a brief overview of some of the more noticable changes:

On the optimization front inter-procedural optimizations (IPO) and profile
driven optimizations (PDO) have been further improved and some classic loop
nest optimization passes have been added: -floop-unroll-and-jam performs
outer loop unrolling and fusing of the inner loop copies, while
-floop-interchange exchanges loops in a loop nest to improve data locality.
These, as well as an improved -ftree-loop-distribution pass are enabled by
default at -O3 and above.

A new pragma "GCC unroll" has been implemented in the C family of languages
as well as Fortran to provide finer-grained control over loop unrolling.

DWARF debugging information in the presence of link-time optimization now
properly preserves language-specific information.  The -gcolumn-info
option is now enabled by default, so column information is part of DWARF
debugging information in addition to filenames and line numbers.

The C family compilers have gained options -Wmultistatement-macros
(warning about unsafe macros expanding to multiple statements used
as a body of a statement such as if, else, while, switch, or for),
-Wstringop-truncation (warning for calls to bounded string manipulation
functions such as strncat, strncpy, and stpncpy that might either truncate
the copied string or leave the destination unchanged), -Wcast-function-type
(warning when a function pointer is cast to an incompatible function pointer,
enabled by -Wextra), and -Wsizeof-pointer-div (warning for suspicious
divisions of the size of a pointer by the size of the elements it points
to, which usually is an indication of a mistaken way to calculate the
number of elements in an array, enabled by -Wall), among others.

The existing -Warray-bounds and -Wrestrict options have been enhanced to
detect many more instances, as have -Wformat-overflow and -Wformat-truncation.

Error messages and warnings better highlight the locations of issues in
many cases, and helpful "fix it" hints are provided more often.

The C++ ABI (-fabi-version=12) introduces minor changes in a few fringe
cases.  The GCC 7 ABI can still be selected with -fabi-version=11.

The C++ frontend as well as libstdc++ feature experimental support for
many C++2a features and Fortran has seen a large number of improvements.

Lots and lots of improvements for Arm and AArch64 targets, as well as
the usual dose on x86 and powerpc.

PR:		229681

1 files changed, 106 insertions, 0 deletions

diff --git a/lang/gcc8/files/patch-arm-unwind-cxx-support b/lang/gcc8/files/patch-arm-unwind-cxx-support
new file mode 100644
index 000000000000..ec6959b9655c
--- /dev/null
+++ b/lang/gcc8/files/patch-arm-unwind-cxx-support
@@ -0,0 +1,106 @@
+--- UTC
+Index: gcc/ginclude/unwind-arm-common.h
+===================================================================
+--- gcc/ginclude/unwind-arm-common.h	(revision 219113)
++++ gcc/ginclude/unwind-arm-common.h	(working copy)
+@@ -82,7 +82,11 @@
+ 
+   struct _Unwind_Control_Block
+     {
++#ifdef __FreeBSD__
++      unsigned exception_class __attribute__((__mode__(__DI__)));
++#else
+       char exception_class[8];
++#endif
+       void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block *);
+       /* Unwinder cache, private fields for the unwinder's use */
+       struct
+@@ -181,7 +185,11 @@
+ 
+   /* Support functions for the PR.  */
+ #define _Unwind_Exception _Unwind_Control_Block
++#ifdef __FreeBSD__
++  typedef unsigned _Unwind_Exception_Class __attribute__((__mode__(__DI__)));
++#else
+   typedef char _Unwind_Exception_Class[8];
++#endif
+ 
+   void * _Unwind_GetLanguageSpecificData (_Unwind_Context *);
+   _Unwind_Ptr _Unwind_GetRegionStart (_Unwind_Context *);
+Index: libstdc++-v3/libsupc++/unwind-cxx.h
+===================================================================
+--- libstdc++-v3/libsupc++/unwind-cxx.h	(revision 219147)
++++ libstdc++-v3/libsupc++/unwind-cxx.h	(working copy)
+@@ -235,7 +235,7 @@
+   return reinterpret_cast<__cxa_dependent_exception *>(exc + 1) - 1;
+ }
+ 
+-#ifdef __ARM_EABI_UNWINDER__
++#if defined(__ARM_EABI_UNWINDER__) && !defined(__FreeBSD__)
+ static inline bool
+ __is_gxx_exception_class(_Unwind_Exception_Class c)
+ {
+@@ -309,13 +309,7 @@
+   c[6] = 'R';
+   c[7] = '\0';
+ }
+-
+-static inline void*
+-__gxx_caught_object(_Unwind_Exception* eo)
+-{
+-  return (void*)eo->barrier_cache.bitpattern[0];
+-}
+-#else // !__ARM_EABI_UNWINDER__
++#else // !__ARM_EABI_UNWINDER__ || __FreeBSD__
+ // This is the primary exception class we report -- "GNUCC++\0".
+ const _Unwind_Exception_Class __gxx_primary_exception_class
+ = ((((((((_Unwind_Exception_Class) 'G' 
+@@ -339,6 +333,16 @@
+     << 8 | (_Unwind_Exception_Class) '+')
+    << 8 | (_Unwind_Exception_Class) '\x01');
+ 
++const _Unwind_Exception_Class __gxx_forced_unwind_class
++= ((((((((_Unwind_Exception_Class) 'G'
++        << 8 | (_Unwind_Exception_Class) 'N')
++       << 8 | (_Unwind_Exception_Class) 'U')
++      << 8 | (_Unwind_Exception_Class) 'C')
++     << 8 | (_Unwind_Exception_Class) 'F')
++    << 8 | (_Unwind_Exception_Class) 'O')
++   << 8 | (_Unwind_Exception_Class) 'R')
++  << 8 | (_Unwind_Exception_Class) '\0');
++
+ static inline bool
+ __is_gxx_exception_class(_Unwind_Exception_Class c)
+ {
+@@ -346,6 +350,12 @@
+       || c == __gxx_dependent_exception_class;
+ }
+ 
++static inline bool
++__is_gxx_forced_unwind_class(_Unwind_Exception_Class c)
++{
++  return c ==  __gxx_forced_unwind_class;
++}
++
+ // Only checks for primary or dependent, but not that it is a C++ exception at
+ // all.
+ static inline bool
+@@ -357,7 +367,18 @@
+ #define __GXX_INIT_PRIMARY_EXCEPTION_CLASS(c) c = __gxx_primary_exception_class
+ #define __GXX_INIT_DEPENDENT_EXCEPTION_CLASS(c) \
+   c = __gxx_dependent_exception_class
++#define __GXX_INIT_FORCED_UNWIND_CLASS(c) c = __gxx_forced_unwind_class 
++#endif // __ARM_EABI_UNWINDER__ && !__FreeBSD__
+ 
++#ifdef __ARM_EABI_UNWINDER__
++static inline void*
++__gxx_caught_object(_Unwind_Exception* eo)
++{
++    return (void*)eo->barrier_cache.bitpattern[0];
++}
++
++#else // !__ARM_EABI_UNWINDER__
++
+ // GNU C++ personality routine, Version 0.
+ extern "C" _Unwind_Reason_Code __gxx_personality_v0
+      (int, _Unwind_Action, _Unwind_Exception_Class,